I need to generate a user interface for entering a sales document (eg invoice). I'm trying to use components of "developer express" specifically the QuantumGrid component (TcxGrid). I've seen the demos of master-detail components and search in the devexpress support center, but none has helped me because all use 2 grids to handle the master-detail relation, and edit multiple records at once.
I just need to edit a record (document) at a time and using a pair of objects dataware components (eg TDBEdit) in the header and a grid to handle the detail.
something like this
Where can I find a basic example of using these components in this way?
Tthe Master/Child properties in the QuantumGrid are mainly designed to nest multiple items in the grid. If you setup the relationship in the data components you can simply hook the controls up to the correct DataSource and everything will work.
So if you have two DataSets Customer and Invoice. The Invoice Master Datasource is the Customer DataSource. Then on your edit controls you point to the Customer DataSource and you point the Grid to the Invoice DataSource.
If you think about what the Master/Detail relationship is doing it really just filters the records on the Detail DataSet to match the current record on the Master DataSet. Individual Edit controls will always display the "current" record in the DataSet they are connected to. Grids will show all visible records in the DataSet they are connected to.
I have a tendency to not use Master/Detail relationships in an edit form like you show here. I'm assuming there is some way on a different screen to pick the invoice to edit. I usually create a copy of the needed DataSets with only the records needed for this edit. If I am editing a existing invoice I copy the current records. If it is a new invoice I can start off with an empty recordset. It is more work - I have some generic library functions that will copy a DataSet Structure and then copy one or more records into that Dataset. Depending on your setup you can also requery your Database to just get the records you are interested in. Obviously that should not be done in all cases. Another issue with this approach is you need a way to update any other Datasets you may have with this data - i.e. your main search screen.
However, once I get on the edit screen I find it makes things eaiser. Now I don't need to worry about the master detail relationship at the top level. If the invoice has internal Master/Detail relationships you can just deal with those, but you know that the DataSets only have the data for this one invoice - not everything in the Database.
In the case of your form if you limit the Data in the DataSets you can just hook everything up directly and it should work as you expect. You would only have one record in the Customer DataSet and the invoice would just have the records for this Invoice.
I think you'll need to take care of the master-detail relations in your ClientDataSource components. The grid will then follow this relation.
Why don't you ask this at support#devexpress.com ?
The reason why I have a vcl subscription is, apart from the quality of the components of course, because they do have a great support site and staff ?
There you ask it directly to the people who have written the stuff, and they are most likely happy to supply you with a sample program (at least I have received a lot of samples over the years).
The premise is the same as with any other master-detail relationship, regardless of the components. You will need to setup the master-detail on the dataset level to accomplish what you want.
Related
I am making a user form in Delphi for documents tracking application. I am interested in functionalities input new entry (record) and view list by... (date, name of document, ID,...).
My problem is that I don't know how to implement these functionalities for more than one user. Currently, I have 5 users. Each user has a unique input data (record) fields (columns) and view fields (columns) of each user are also unique. There could be more users.
So, how to implement these functionalities for this form? How to assign different data (fields) for each separate user for input and view? That is what I don't understand. Is that distributed functionality of an application? If yes, how to achieve it?
Note that I don't want static assigning of a user in application's code, e.g:
if(username='user1') then {
input();
view();
}
else if (username='user2') then {...}
...
because, than, every time there is a new user, developer must go back to the application's code and hard-code it. That is not efficient and is a bad implementation. Rather, I want that to be dynamic (if that is the right term). How to achieve this?
Note: I am using dbExpress tool with MySQL DBMS with RAD Studio XE7 Architect.
If I'm correctly understanding what you are asking, it seems as if you are unfamiliar with the idea of tables/datasets which operate in a so-called Master-Detail relationship. These are very easy to set up in Delphi.
Once you get familar with M->D relationships, I think you'll realise that what you should have been asking about is how to set one up in your app, rather than the problem of hard-coding of individual users into your form.
In your case, what you are missing at the moment is a table of users' details. Let's call that the Users table. Usually this would contain their name, obviously, and some kind of unique identifier (best is a "Primary key" in the Users database table), but NOT, please, their password to access the db, especially not in plain text.
Once your Users table is created, you can create a display grid (TDBGrid) and input/editing form for it.
Then, if you don't have it already, you could set up a grid and editing form for users' documents (which I'm going to refer to as the Documents table).
Once that's done, the main thing left to do is to set up in your Delphi project a Master-Detail relationship between your Users table (the master) and your Documents table (the detail).
If you prefer you can have a single form with two grids, the Users grid and the Documents grid on it, and as you scroll through the Users grid, you'll see that the Documents grid shows only their document records.
The details of how to set up a Master-Detail vary somewhat according to the type of table/dataset you're using so you'll need to search online for the details of how to do it. Broadly, it's a matter of connecting a TDataSource to your Users table and setting the DataSource (or MasterSource) property of your Documents table to point at the Users TDataSource, and then setting a couple of other, table-type-dependent properties of the Documents table.
Every edition of Delphi since well before D7 has come with a demo app, "MastApp" which illustrates how you use Master-Detail relationship amongst a number of tables. I suggest you take a look at the MastApp for your Delphi version and then look into how to set up M->D relationships for the type of Delphi dataset you are actually using.
I'm using Firebase database for my application, and basically people post new chapters of different series into the app.
So, I have one parent called "series" which hosts information about the different series:
Then, I have one parent called "chapters" which contains many different children that are the different series keys, and under them are many chapters (so the chapters are under each series).
However, I also want to have a section of the app where the user can view all newly added chapters across all different series, so I made a "latestReleases" parent, which automatically gets added to whenever a new chapter is added to "chapters."
However, the way I am currently displaying latestReleases is to add the entirely of "latestReleases" to an array and then sort by date. Although with a small amount of chapters this works fine, there are now thousands of chapters, so there are thousands of things in latestReleases. Therefore, it takes literally forever for it to load. There must be a better way to do this, correct? I feel like a better way would be to only load part of the latestReleases, and then the user can choose to load more incrementally. However, it this possible? How else would I be able to achieve this? Would I need to create several "latestReleases" parents that get updated automatically? Thanks!
Does anyone know how to write a script that will allow me to have a list become visible based on the text in a particular cell in my sheet?
Here is what I am trying to do: I am trying to create personalized book lists for my students based on the specific classes they are enrolled in. So, when I choose the class, I would like the book list to automatically populate so that I can create a list for each student without much time involved for each student. Also, some classes may involve multiple books, so these would need to be on separate lines in the spreadsheet. Is this even possible?
I hope this will help you just go your sheet Data -> Validation then you can create Dropdownbox so to achieve your requirement create two sheet in your working sheet then give validation finally do a connection with classes and books
I am building an mvc 3 application that will be multi-tenant, which means it will use the same basic data structure, but provide different data depending on the domain name used to access it.
A problem I am trying to solve is this. How best do I populate a number of dropdown lists with selection choices based on the site being rendered. To add another wrinkle, I will need to localize the strings as well.
An obvious choice is to simply create a table with columns for website id and language id, plus field id and string value. This seems ok, but also seems to ignore possible mechanisms that are already in place for localization. I feel like i'm recreating the wheel here.
As an example, site 1 might have a dropdownlist for Favorite Activities, and have ranges items that are geared toward musical interests. Site 2 might have the same dropdown, but have items geared for sports intersts.
So my question is, how would you go about solving this problem? Also, in a similar vein... If you have selection lists, say State codes, cities, etc.. would you tend to create seperate tables to populate this data (states table, cities table, etc..) or would you put all this information in a common table and have an ID to indicate which dropdown it was to be used for? The former seems more normalized, but the latter seems more efficient (less code to write).
Thoughts about Common Lookup Tables. This guy is definitely against.
http://www.projectdmx.com/dbdesign/lookup.aspx
I have used it and believe that I have saved some time, or at least some keystrokes. Might be sorry later on.
I haven't even attempted this yet and am creating this question for advice really.
I have a strongly typed page which receives a form model composed of several components. It is to create a mitigating circumstance (MC) for a student at a university for my final year project. A MC can be composed of the initial problem, assessment extensions, and I use a multi select box to allow the user to select staff retrieved from the database which are able to view the MC once created.
The thing is I feel that a student could be granted many assignment extensions for one problem. I am wander if it is possible to include a button/image on the form which when clicked will create a new assessment extension object, and duplicate the form components to set the values for the object? This would all need to occur without any page refreshes.
Any advice, or links to good tutorials would be appreciated. I have so far been unable to find any suitable examples.
Thanks,
Jon
There are a number of ways to do this, but the fastest is to create a javascript handler which creates the form controls without any sort of server request, all you need to do is keep track of how many items are in your list so you can name the form controls correctly.
Start by making a button that when you click on it creates form controls. Once you get that, work on the naming.